One thing that has helped me with cleaning up lines and eye-training is: doing more extremely short (~15 second) quick drawing sessions, so that I don't have time to re-draw or clean up lines. For proportion, maybe starting with a bounding box with mid-lines? The only proportion issues that stand out to me are some of the upright poses - these get me every time! Really, really nice work, though! I think your gesture work is amazing!